AC weirdness

[KeZu01]

More issues!
Last month the a/c compressor died on my xj, it wouldn't spin, with ac on or off, and was killing the engine bad. Had a shop replace the compressor and charge it.
Today the ac wasn't blowing cold so I looked under the hood. Alas, there the a/c compressor wheel was again randomly stopping while running. Just does it when a/c is running now, so maybe not the same issue?
What's going on, could something else wrong with my jeep be causing it to kill ac compressors? The belt is fresh and just about everything else there is new too.
The shop was out of town as I was on vacation, or I would just take it in to them to ask what's up.

Jeep is a 2001 xj, 4.0, aw4, 4x4.

[4.3LXJ]

The whole thing, or is the clutch disengaging?

[KeZu01]

Ah, update. Last time the whole thing was seizing and that's why it was killing the engine.
This time what I thought was it seizing is just the compressor kicking off. Clutch spins fine no problem, but turn on the ac and the compressor wheel starts to spin then stops and the clutch just free wheels like it is off. Thus no cold air.

Any ideas?

[4.3LXJ]

This is a classic symptom of being undercharged. Probably just a little low on refrigerant. Might have a leak in it

[KeZu01]

Yep, had it tested for leak, sure thing, it didn't hold pressure very well. And I just replaced that compressor, now no AC. Oh well, will wait on it till spring probably.
Any common culprits for AC leaks on these? I imagine I will just have to do a leak down test of some sort.

[4.3LXJ]

All the O rings at the fittings. Look for a tell tale oil stain around them